Adhesive resin composition, laminated sheet and lid material using said composition

Abstract

To provide an adhesive resin composition exhibiting easy openability in opening, a laminated sheet using the composition and a lid material, more specifically, an adhesive resin composition which has easy openability, especially, for polyethylene or a container coating polyethylene without restricting a lamination method by lamination and a substrate material, and prevents stringiness, a laminated sheet using the composition, and a lid material.SOLUTION: An adhesive resin composition contains, in 100 mass% of the total of a polyethylene-based resin (A) having a melt flow rate measured under conditions of 190°C and a load of 2.16 kg of 0.1-10 g / 10 min, a polypropylene-based resin (B) having a melt flow rate measured under conditions of 190°C and a load of 2.16 kg of 0.1-10 g / 10 min, and a polyethylene wax (C), 35-70 mass% of a polyethylene-based resin (A), 15-40 mass% of a polypropylene-based resin (B) and 8-40 mass% of a polyethylene wax (C).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an adhesive resin composition that exhibits easy-open properties by undergoing cohesive failure when opened, and a sheet laminated with a coating of the adhesive resin composition. More specifically, the present invention relates to an adhesive resin composition that exhibits easy-open properties and does not cause stringiness, particularly for polyethylene or polyethylene-coated containers, without limiting the lamination method or base material, and a laminate sheet laminated with a coating of the adhesive resin composition. [Background technology]

[0002] In the field of food packaging, a widely used packaging format has been to fill contents such as instant ramen, yogurt, and jelly into a paper container coated with a polyethylene resin, and then adhere a lid material having a layer of an adhesive resin composition with excellent sealing properties to the opening of the container.

[0003] In recent years, when opening a lid material from a paper container coated with a polyethylene resin, the adhesive resin composition layer has become the mainstream for its cohesive failure type in order to provide an easy-open function. In the cohesive failure type peeling mechanism, cohesive failure is caused by the blending of two thermoplastic resin components that make up the adhesive resin composition, which are incompatible or partially compatible, resulting in a smooth peeling feel and easy-opening properties. However, this can sometimes cause "stringing," in which the adhesive resin composition remains in the form of threads on the flange of the container.

[0004] If the adhesion between the base material and the adhesive resin composition of a lid material composed of a substrate / base material / adhesive resin composition is insufficient, part of the adhesive resin composition will not undergo cohesive failure but will be pulled toward the container, eventually stretching and breaking, causing stringiness.

[0005] Therefore, a resin composition has been proposed in which an ethylene-α-olefin copolymer acting as a compatibilizer is added to an incompatible or partially compatible two-component thermoplastic resin (see Patent Document 1).

[0006] Furthermore, an easily peelable adhesive for polyethylene has been proposed, which is composed of a polyethylene resin, a crystalline polypropylene resin, and a low-molecular-weight polyethylene wax (see Patent Document 2).

[0007] In addition to incompatible low-density polyethylene and polybutene, sealant adhesives have been proposed that consist of ethylene copolymers such as ethylene-vinyl acetate copolymer, ethylene-methyl methacrylic copolymer, and ethylene-methacrylic acid copolymer and wax (see Patent Document 3).

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-302990 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-112955 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-166304 Summary of the Invention [Problem to be solved by the invention]

[0009] The main method for laminating an adhesive resin composition to produce a substrate / undercoat / adhesive resin composition laminate is the lamination method, which can be broadly classified into three methods: extrusion lamination, in which a molten adhesive resin composition is laminated onto the substrate / undercoat, co-extrusion lamination, in which two layers of a molten adhesive resin composition and an undercoat are simultaneously laminated onto the substrate, and dry lamination, in which a solvent-based adhesive is applied to the undercoat of the substrate / undercoat and then the molten adhesive resin composition is laminated onto the substrate / undercoat. Co-extrusion lamination involves extruding two layers simultaneously, so it is necessary to select and consider a base material that matches the properties of the adhesive resin composition. Dry lamination also has problems, such as reduced workability due to the drying process, which requires removing the solvent from solvent-based adhesives. Extrusion lamination, on the other hand, can solve these problems. On the other hand, in co-extrusion lamination, the base material and the adhesive resin composition are melted and laminated simultaneously, so the adhesive resin composition and the base material are integrated, and stringing can be suppressed. Furthermore, in dry lamination, the base material and the adhesive resin composition are bonded together with an adhesive, so they are sufficiently bonded and stringing can be suppressed. In contrast, in extrusion lamination, a molten adhesive resin composition is laminated on the base material, so there is a problem that the adhesion is insufficient depending on the composition of the adhesive resin composition and the type of base material. In particular, extrusion laminates may not adhere well to the polyethylene (PE) substrate. This is due to the high melting point and crystallinity of polyethylene, and to address this issue, ethylene-acid-modified copolymers such as ethylene-vinyl acetate copolymer (EVA), ethylene-(meth)acrylic acid copolymer, and ethylene-maleic acid copolymer are used as substrates, as they have a relatively low melting point and crystallinity and improve adhesion. The resin composition proposed in Patent Document 1 exhibits good stringiness when produced by co-extrusion lamination, but exhibits stringiness when produced by extrusion lamination. The easily peelable adhesive for polyethylene proposed in Patent Document 2 improves stringiness by laminating using extrusion lamination, but the easily peelable adhesive for polyethylene is laminated to the EVA layer of polyethylene terephthalate (hereinafter also referred to as PET) / PE / EVA, and does not adhere when laminated to the polyethylene layer of PET / PE. The sealant adhesive proposed in Patent Document 3 uses an ethylene copolymer such as an ethylene-vinyl acetate copolymer, an ethylene-methyl methacrylic copolymer, or an ethylene-methacrylic acid copolymer, which contains an acid. This raises concerns about new problems, such as problems in food applications with strong odors and the generation of gel during extrusion lamination. For these reasons, there has been no adhesive resin composition that is highly safe for food and that is not limited in terms of lamination method or base material.

[0010] The problem to be solved by the present invention relates to an adhesive resin composition that exhibits easy-open properties when opened, and a laminate sheet having a coating of the adhesive resin composition laminated thereon. More specifically, the object of the present invention is to provide an adhesive resin composition that exhibits easy-open properties and does not cause stringiness, particularly for polyethylene or polyethylene-coated containers, without restricting the lamination method or base material used, and a laminate sheet having a coating of the adhesive resin composition laminated thereon. [Means for solving the problem]

[0011] As a result of extensive investigations into solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by an adhesive resin composition characterized by containing 35 to 70 mass% of polyethylene resin (A), 15 to 40 mass% of polypropylene resin (B), and 8 to 40 mass% of polyethylene wax (C), relative to a total of 100 mass% of polyethylene resin (A) having a melt flow rate of 0.1 to 10 g / 10 min measured under conditions of 190°C and a load of 2.16 kg, polypropylene resin (B) having a melt flow rate of 0.1 to 10 g / 10 min measured under conditions of 230°C and a load of 2.16 kg, and polyethylene wax (C). Conventionally, polyethylene wax (C) has softened polyethylene resins and reduced their cohesive strength, thereby improving stringiness. However, in the present invention, in addition to the above, by including 8% by mass or more of polyethylene wax (C), the wax imparts wettability to the base material, thereby adhering to the adhesive resin composition, and the base material and the adhesive resin composition are sufficiently bonded together, thereby further improving stringiness. On the other hand, since the inclusion of polyethylene wax (C) significantly reduces the coatability of the extrusion laminate, the problem of coatability can be solved by limiting the melt flow rate of the polyethylene resin (A) measured under conditions of 190°C and a load of 2.16 kg and the melt flow rate of the polypropylene resin (B) measured under conditions of 230°C and a load of 2.16 kg to 0.1 to 10 g / 10 min. As a result, it is possible to provide an adhesive resin composition that is easy to open and does not produce stringiness, without restricting the lamination method or the base material.

[0012] That is, the present invention relates to the following inventions [1] to [5].

[0013] [1] The adhesive resin composition comprises: a polyethylene resin (A) having a melt flow rate of 0.1 to 10 g / 10 min measured at 190°C under a load of 2.16 kg; a polypropylene resin (B) having a melt flow rate of 0.1 to 10 g / 10 min measured at 230°C under a load of 2.16 kg; and a polyethylene wax (C), the total of which is 100% by mass; and the composition contains 35 to 70% by mass of the polyethylene resin (A), 15 to 40% by mass of the polypropylene resin (B), and 8 to 40% by mass of the polyethylene wax (C).

[0014] [2] The adhesive resin composition, wherein the content ratio of the polyethylene resin (A) to the polypropylene resin (B) is (A) > (B), and the content ratio of the polyethylene resin (A) to the polyethylene wax (C) is (A) > (C).

[0015] [3] The adhesive resin composition, wherein the adhesive resin composition has a melt flow rate of 5 to 45 g / 10 min, measured under conditions of 190° C. and a load of 2.16 kg.

[0016] [4] A laminate sheet in which a coating of the adhesive resin composition is laminated on a substrate sheet.

[0017] [5] A lid material formed from the above laminated sheet. [Effects of the Invention]

[0018] The adhesive resin composition of the present invention makes it possible to obtain an adhesive resin composition that is easy to open and does not cause stringiness, and a container having a laminate sheet coated with the adhesive resin composition, without restricting the lamination method or base material used for polyethylene-coated containers. DETAILED DESCRIPTION OF THE INVENTION

[0019] The adhesive resin composition of the present invention contains 35 to 70 mass% of a polyethylene resin (A) having a melt flow rate (hereinafter referred to as MFR) of 0.1 to 10 g / 10 min measured under conditions of 190°C and a load of 2.16 kg, 15 to 40 mass% of a polypropylene resin (B) having an MFR of 0.1 to 10 g / 10 min measured under conditions of 230°C and a load of 2.16 kg, and 8 to 40 mass% of a polyethylene wax (C). The adhesive resin composition of the present invention, the laminated sheet obtained by laminating the composition, the container lid material produced from the laminated sheet, and the container sealed with the lid material will be described in further detail below.

[0020] <Polyethylene resin (A)> The polyethylene resin (A) has an MFR of 0.1 to 10 g / 10 min, more preferably 0.5 to 8 g / 10 min, measured at 190°C under a load of 2.16 kg. A MFR within the above range is preferred in terms of stabilizing coating by extrusion lamination.

[0021] The polyethylene resin (A) may be an ethylene homopolymer or a copolymer of ethylene and an olefin. Specifically, as long as an incompatible or partially compatible system can be maintained, a homopolymer such as low-density polyethylene or high-density polyethylene, or a copolymer obtained by polymerizing ethylene and at least one member selected from the group consisting of propylene, butene, pentene, hexene, or a long-carbon-chain olefin having seven or more carbon atoms in any ratio, can be used. Among these, low-density polyethylene is preferred from the viewpoint of extrusion lamination processability, and low-density polyethylene produced by a high-pressure method is particularly preferred.

[0022] The polyethylene resin (A) accounts for 35 to 70% by mass, preferably 40 to 65% by mass, and more preferably 45 to 60% by mass, of the total 100% by mass of the polyethylene resin (A), polypropylene resin (B), and polyethylene wax (C). Having the polyethylene resin (A) at 35% by mass or more allows for stable coating by extrusion lamination. Having the polyethylene resin (A) at 70% by mass or less allows for sufficient adhesion without impairing easy-openability due to cohesive failure.

[0023] <Polypropylene resin (B)> The polypropylene resin (B) has an MFR of 0.1 to 10 g / 10 min, more preferably 0.5 to 8 g / 10 min, measured at 230°C under a load of 2.16 kg. A MFR within the above range is preferred in that it allows for stable coating by extrusion lamination.

[0024] The polypropylene resin (B) may be a propylene homopolymer or a copolymer of propylene and an olefin. Specifically, as long as an incompatible or partially compatible system can be maintained, a propylene homopolymer or a copolymer obtained by polymerizing propylene and at least one member selected from the group consisting of ethylene, butene, pentene, hexene, or an olefin having a long carbon chain of 7 or more carbon atoms in any ratio can be used. Among these, a polypropylene-ethylene copolymer is preferred from the viewpoint of coatability by extrusion lamination. In this specification, ethylene and propylene copolymers are classified as polyethylene resins (A) when their DSC melting points are 130°C or lower, and as polypropylene resins (B) when their DSC melting points are higher than 130°C.

[0025] The polypropylene resin (B) is preferably 15 to 40% by mass, more preferably 18 to 35% by mass, and particularly preferably 20 to 30% by mass, based on 100% by mass of the total of the polyethylene resin (A), the polypropylene resin (B), and the polyethylene wax (C). A content within the above range is preferred in terms of ease of opening.

[0026] <Polyethylene wax (C)> The polyethylene wax (C) can provide sufficient lamination strength, particularly when the base material is polyethylene, and can also improve stringiness. The polyethylene wax (C) may be an ethylene homopolymer or copolymer. Specifically, polyethylene, polyethylene oxide, ethylene-acrylic acid copolymer, ethylene-vinyl acetate copolymer, ethylene oxide-vinyl acetate copolymer, or ethylene-maleic anhydride copolymer can be used as long as it is compatible with the polyethylene resin (A) and can impart wettability to the base material. Among these, polyethylene homopolymer is preferred from the standpoint of odor. However, the polyethylene wax (C) does not contain the polyethylene resin (A). The polyethylene wax (C) in the present invention is preferably 8 to 40% by mass, more preferably 12 to 30% by mass, and particularly preferably 15 to 25% by mass, based on 100% by mass of the total of the polyethylene resin (A), the polypropylene resin (B), and the polyethylene wax (C). The amount within the above range is preferable in terms of adhesion to the polyethylene of the base material and improvement of stringiness.

[0027] The viscosity of the polyethylene wax (C) at 140°C is preferably 50 to 10,000 mPa·s, more preferably 60 to 8,000 mPa·s. A viscosity within this range is preferable in terms of sufficient adhesion to the polyethylene base material. The viscosity was measured using a Brookfield viscometer (measurement conditions: 140°C, rotor No. 3, 12 rpm, 30 seconds). Details are described in the Examples section.

[0028] The melting point of the polyethylene wax (C) is preferably 90 to 145°C, more preferably 95 to 130°C. A melting point within the above range is preferred in that it adheres sufficiently to the polyethylene of the base material. The melting point in the present invention is a temperature measured by a differential scanning calorimeter. Details will be described in the Examples section.

[0029] <Adhesive resin composition> The adhesive resin composition of the present invention comprises, in a total of 100 mass% of the polyethylene resin (A), the polypropylene resin (B), and the polyethylene wax (C), 35 to 70 mass% of polyethylene resin (A), 15 to 40% by mass of a polypropylene-based resin (B), and The polyethylene wax (C) is contained in an amount of 8 to 40 mass %. Furthermore, it is preferable that the content ratio (mass ratio) of the polyethylene resin (A) to the polypropylene resin (B) is (A) > (B), and the content ratio (mass ratio) of the polyethylene resin (A) to the polyethylene wax (C) is (A) > (C).

[0030] The adhesive resin composition of the present invention may contain resins other than the polyethylene-based resin (A), the polypropylene-based resin (B), and the polyethylene wax (C) within a range that does not contradict the object of the present invention, i.e., within a range that does not impair the easy-open property and stringiness.

[0031] Specific examples of such resins include maleic acid-modified products obtained by adding maleic anhydride to at least one selected from the group consisting of ethylene or long-carbon-chain olefins having three or more carbon atoms; ethylene-unsaturated monocarboxylic acid copolymers such as ethylene-vinyl acetate copolymers, ethylene-acrylic acid copolymers, and ethylene-(meth)acrylic acid copolymers, and metal salts thereof; styrene-butadiene copolymer elastomers and hydrogen adducts thereof; known tackifying resins such as aliphatic hydrocarbon resins, alicyclic hydrocarbon resins, aromatic hydrocarbon resins, polyterpene resins, and rosins; and known waxes such as polypropylene wax, ethylene-vinyl acetate copolymer wax, Fischer-Tropsch wax, paraffin wax, oxidized wax, maleic acid-modified wax, and polyethylene wax grafted with a styrene monomer. These resins may be used alone or in combination of two or more.

[0032] The adhesive resin composition of the present invention may further contain additives, etc., to prevent thermal deterioration, thermal decomposition, blocking, etc., and to ensure suitability for processing such as film processing, extrusion lamination, etc., within the scope of the present invention. Examples of additives include organic lubricants such as erucic acid amide, inorganic lubricants such as calcium carbonate, antioxidants such as hindered phenols, as well as other antiblocking agents, antistatic agents, fillers, pigments, etc.

[0033] The amount of the additives to be added is 0% by mass or more and less than 15% by mass, preferably 0% by mass or more and less than 10% by mass, and more preferably 0% by mass or more and less than 5% by mass, relative to 100% by mass of the total of the polyethylene resin (A), the polypropylene resin (B), and the polyethylene wax (C). A content within the above range is preferred because it does not impair the easy-open property or stringiness.

[0034] These additives may be added when the polyethylene resin (A), the polypropylene resin (B), and the polyethylene wax (C) are blended, or may be kneaded in advance into any of the polyethylene resin (A), the polypropylene resin (B), and the polyethylene wax (C), and then the polyethylene resin (A), the polypropylene resin (B), and the polyethylene wax (C) into which the additives have been kneaded are blended with other components.

[0035] The polyethylene resin (A), polypropylene resin (B), polyethylene wax (C), and optional additives are blended, for example, by adding these components to a mixing device such as a Henschel mixer or a tumbler mixer, mixing them for 5 to 20 minutes, then placing them in an extruder, kneading them under heat, and then extruding them. The extrudate is usually pelletized and used in subsequent processes. A preferred example of the extruder is a twin-screw extruder, but this is not limiting. Furthermore, extrusion is usually carried out at 140 to 200°C.

[0036] The adhesive resin composition preferably has a melt flow rate of 5 to 45 g / 10 min, more preferably 8 to 35 g / 10 min, and even more preferably 10 to 30 g / 10 min, measured at 190°C under a load of 2.16 kg. A melt flow rate in the above range is preferred in terms of stable coating by extrusion lamination.

[0037] <Laminated sheet> Next, a laminate sheet in which a coating of the adhesive resin composition of the present invention is laminated on a substrate sheet will be described. Examples of substrate sheets that can be used include paper, aluminum, polyester, polyethylene, polypropylene, polystyrene, aluminum-deposited polyester, aluminum-deposited polypropylene, and silica-deposited polyester. The substrate sheet does not need to be a single layer, and may be a laminate of two or more layers. In the present application, it is preferable to use, for example, a laminate of PET with a thickness of 5 to 20 μm and polyethylene with a thickness of 5 to 30 μm. The surface of the laminate that comes into contact with the adhesive resin composition is called the base material. The adhesive resin composition of the present invention can be laminated on a substrate by, for example, forming the pelletized resin composition as described above into a single-layer film by inflation or casting, and laminating this film on a substrate sheet (via an adhesive layer, if necessary). Alternatively, the kneaded composition may be directly coated on the substrate, or other methods may be used.

[0038] To improve the adhesiveness of the laminated surface, the substrate sheet surface may be subjected to flame treatment, ozone treatment, corona discharge treatment, or treatment with an anchor coating agent. Direct extrusion lamination is also possible for a substrate sheet pre-laminated with a polyethylene-based resin. Alternatively, a multilayer film may be formed by co-extrusion with polyethylene or polypropylene, and then laminated with a stretched or unstretched film such as a polyester film, polyamide film, or polypropylene film by dry lamination or sand lamination to obtain a laminated film. In this case, too, if necessary, the substrate sheet surface may be subjected to flame treatment, ozone treatment, corona discharge treatment, treatment with an anchor coating agent, or the like to improve the adhesiveness of the laminated surface. The thickness of the adhesive resin composition layer of the present invention is 5 μm or more, preferably 10 μm or more. The laminate sheet of the present invention includes long and short cut films and sheets. The base sheet also includes a single layer and a laminate consisting of multiple layers. The laminate sheet laminated with the adhesive resin composition of the present invention can be used as a lid material as described below, and can also be suitably used as a sealant film for bags (sealed with the adhesive resin composition side as the inner surface).

[0039] <Lid material> The laminated sheet of the present invention is suitably used as a lid material by being cut to fit the shape of the opening of the container body to be sealed. The lid material of the present invention is preferably a laminate of PET and polyethylene, with a 5 to 40 μm coating of the adhesive resin composition of the present invention laminated on the polyethylene surface.

[0040] <Container body> The container body is preferably made of a polyethylene resin, or the inner surface of which is covered with a polyethylene resin.

[0041] <Openable sealed container> The openable sealed container has the opening of the container body sealed with a lid cut to fit the shape of the opening of the container body. That is, the adhesive resin composition of the present invention, which is disposed on one side of the lid, is brought into contact with the adhesive surface (also called a flange) of the opening of the sealed container and heated to bond them together. The bonding conditions are preferably 130 to 170°C. When the container body is a PET container, it is preferable that the container body and the lid material are thermally bonded at a thermal bonding temperature of 130 to 170°C, the opening strength at room temperature is in the range of 10 to 20 N, and it is also preferable that the thermal adhesive layer peels at the interface when peeled. The resealable seal of the present invention can be used to package, for example, jelly, pudding, yogurt, frozen desserts, dried snacks, instant noodles, etc. [Example]

[0042] The present invention will be described below based on examples, but the present invention is not limited thereto. In the examples, "parts" and "%" represent "parts by mass" and "% by mass", respectively.

[0043] The MFR, viscosity, and melting point were measured by the following methods.

[0044] [MFR] In accordance with JIS K7210, a melt indexer L244 (manufactured by Takara Kogyo Co., Ltd.) was used to fill the sample into a cylinder with an inner diameter of 9.55 mm and a length of 162 mm. After melting at 190°C or 230°C, a load was applied evenly using a plunger weighing 2.16 kg and having a diameter of 9.48 mm, and the amount of resin extruded per unit time (g / 10 min) was measured from an orifice with a diameter of 2.1 mm located in the center of the cylinder.

[0045] [viscosity] Measurement was carried out using a VISCOMETER TVB-10 (a B-type viscometer manufactured by TOKI SANGYO) at a temperature of 140°C or 180°C, with a rotor No. 3 at 12 rpm for 30 seconds.

[0046] [DSC melting point] Using a DSC-60A plus (Shimadzu Corporation differential scanning calorimeter), approximately 5 mg of sample was weighed onto an aluminum pan and measured under a nitrogen stream at a temperature range of 0°C to 200°C at a heating rate of 10°C / min, and the maximum value of the endothermic curve was determined.

[0047] <Method for producing adhesive resin composition> [Example 1] The polyethylene resin (A), polypropylene resin (B), polyethylene wax (C), and additives were preblended for 5 minutes in a Henschel mixer in the amounts shown in Table 1. The preblend was placed in a hopper and fed to the following extruder using a screw feeder to obtain the adhesive resin composition of Example 1. <Extruder conditions> Extruder: IKG PMT32-40.5 co-rotating twin-screw extruder Barrel temperature: 180°C (feed inlet 160°C) Screw rotation speed: 200 rpm Feeding rate: 10kg / hr

[0048] [Examples 2 to 14 and Comparative Examples 1 to 9] According to the compositions in Tables 1 and 2, adhesive resin compositions of Examples 2 to 14 and Comparative Examples 1 to 9 were obtained in the same manner as in Example 1.

[0049] <Evaluation of Adhesive Resin Composition> The MFR of the adhesive resin composition was measured. Furthermore, a laminated sheet (lid material) was prepared as follows, and the laminated sheet was used to evaluate lamination strength (adhesion to the base material), stringiness (resistance to adhesion to the container), and opening strength (ease of opening) according to the following methods and criteria. The results are shown in Table 1.

[0050] (Method for manufacturing laminated sheet (lid material)) The adhesive resin composition thus obtained was laminated to a thickness of 20 μm on the PE side (undercoat) of a PET 20 μm / PE 12 μm substrate sheet using an extrusion laminator, to prepare a laminate sheet. The processing conditions are shown below. Extrusion laminator: Musashino Kikai 400M / M Test EXT laminator Resin temperature directly below the die: 250℃~280℃ Machining speed: 30m / min T-die width: 400mm Cooling roll surface temperature: 20℃

[0051] <Coatability> The coatability using an extrusion laminator was evaluated according to the following criteria. 〇: Die discharge width - actual coating width = less than 50 mm: Good △: Die discharge width - actual coating width = 50mm to 100mm: Usable ×: Die discharge width - actual coating width = over 100 mm: defective

[0052] <Lamination strength (adhesion to the base material)> The resulting laminated sheet (covering material) was cut to a size of 50 mm x 70 mm, and the base material layer and the adhesive resin composition layer were manually peeled off to a size of 50 mm x 20 mm. Measurements were carried out in a constant temperature and humidity chamber at a temperature of 23°C and a humidity of 65% under conditions of T-peel and a pulling speed of 200 mm / min, and the average value was taken as lamination strength. The adhesion to the base material was evaluated according to the following criteria. ◯: The adhesive resin composition layer and the base material layer could not be peeled off. △: Opening strength is 1.5N / 50mm or more, or the adhesive resin composition layer is broken: usable ×: Opening strength is less than 1.5N / 50mm: Defective -: Measurement not possible because coating was not possible <Stringiness (anti-container adhesion)> When the opening strength was measured, the presence or absence of the adhesive resin composition on the flange of the PET container was visually confirmed, and the result was evaluated according to the following criteria. ◯: No adhesive resin composition on the flange: Good △: A small amount of adhesive resin composition was observed on the flange: Usable ×: Adhesive resin composition was observed on the flange: poor -: Unable to measure because lamination strength was not obtained (the adhesive resin composition did not adhere to the base material)

[0053] <Opening strength (easy opening)> The resulting laminated sheet (lid material) was cut into a size of 90 mm x 90 mm, and the adhesive resin composition surface was heat-bonded to a 71Φ PET container at a gauge pressure of 0.3 MPa, 150°C, and 1 second to seal the container. The container was left in a constant temperature and humidity chamber at a temperature of 23°C and a humidity of 65% for 24 hours, and then measurements were made in the same constant temperature and humidity chamber under conditions of a 45° angle peel and a pulling speed of 200 mm / min. The maximum value was taken as the opening strength, and the ease of opening was evaluated according to the following criteria. 〇: Opening strength is 10N or more but less than 20N: Good △: Opening strength is 7N or more but less than 10N, or 20N or more but less than 25N: Usable ×: Opening strength is less than 7N or 25N or more: Defective -: Unable to measure because lamination strength was not obtained (the adhesive resin composition did not adhere to the base material)

[0054] [Table 1]

[0055] [Table 2]

[0056] The raw material abbreviations used in Tables 1 and 2 are listed below. A1: HP0830NN (SABIC low-density polyethylene, MFR 0.8g / 10min measured at 190℃ and a load of 2.16kg) A2: HP7022 (SABIC, ethylene-propylene copolymer, MFR measured at 190°C under a load of 2.16 kg, 7 g / 10 min, DSC melting point 108°C) A3: LDF260YZ (Lotte Chemical Titan, low-density polyethylene, MFR 5g / 10min measured at 190℃ and a load of 2.16kg) A4: XJ700 (LOTTE, low-density polyethylene, MFR 24g / 10min measured at 190℃ and a load of 2.16kg)

[0057] B1: B-110 (manufactured by LOTTE, polypropylene, MFR 0.5 g / 10 min measured at 230 °C and a load of 2.16 kg) B2: SB-520 (manufactured by LOTTE, propylene-ethylene copolymer, MFR measured at 230°C under a load of 2.16 kg, 2 g / 10 min, DSC melting point 150°C) B3: 513A (SABIC, polypropylene, MFR 6g / 10min measured at 230℃ and 2.16kg load) B4: J-360 (LOTTE Corporation, propylene-ethylene copolymer, MFR measured at 230°C under a load of 2.16 kg: 18 g / 10 min, DSC melting point: 148°C)

[0058] C1: L-C102N (LION CHMTECH, polyethylene wax, viscosity 350 mPa·s (140°C), melting point 107°C) C2: A-C735 (Honeywell, polyethylene wax, viscosity 6,000 mPa·s (140°C), melting point 110°C) C3:200P (Mitsui Chemicals, polyethylene wax, viscosity 80 mPa·s (140°C), melting point 130°C) C4: 4051E (Mitsui Chemicals, oxidized polyethylene wax, viscosity 500 mPa·s (140°C), melting point 120°C) C5: Sasol H1 (Sasol, paraffin wax, viscosity 8 mPa·s (140°C), melting point 70°C) C6: NP055 (Mitsui Chemicals, polypropylene wax, viscosity 50 mPa·s (180°C), melting point 150°C)

[0059] Anti-blocking agent: Incrosslip C (manufactured by Croda, erucic acid amide) 0.1% externally added Antioxidant: IRGANOX 1010 (BASF, hindered phenol) 0.1% externally added

[0060] As shown in Tables 1 and 2, in comparison with Comparative Examples 1 to 9, Examples 1 to 14, which contain specific resins (A) to (C) in specific ratios, demonstrate that the base material exhibits sufficient lamination strength against polyethylene, thereby suppressing stringiness and achieving both excellent ease of opening.

Claims

1. An adhesive resin composition comprising: a polyethylene resin (A) (excluding ethylene-vinyl acetate copolymers) having a melt flow rate of 0.1 to 10 g / 10 min measured at 190°C under a load of 2.16 kg; a polypropylene resin (B) having a melt flow rate of 0.1 to 10 g / 10 min measured at 230°C under a load of 2.16 kg; and a polyethylene wax (C), the total amount of which is 100% by mass; 35 to 70% by mass of the polyethylene resin (A), 15 to 40% by mass of the polypropylene resin (B), and 8 to 40% by mass of the polyethylene wax (C).

2. 2. The adhesive resin composition according to claim 1, wherein the content ratio of the polyethylene resin (A) to the polypropylene resin (B) is (A) > (B), and the content ratio of the polyethylene resin (A) to the polyethylene wax (C) is (A) > (C).

3. 3. The adhesive resin composition according to claim 1, wherein the adhesive resin composition has a melt flow rate of 5 to 45 g / 10 min measured under conditions of 190° C. and a load of 2.16 kg.

4. A laminated sheet comprising a substrate sheet and a coating of the adhesive resin composition according to any one of claims 1 to 3 laminated thereon.

5. A lid material comprising the laminated sheet according to claim 4.

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